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Chinese Journal of Catalysis 2017年第9期38卷 1460-1472页

作者： jingyue (Jimmy) Liu Department of Physics Arizona State University Tempe Arizona 85287 United States State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 LiaoningChina

近年来,"单原子催化"逐渐得到人们的认可与关注,成为催化领域新的前沿与热点之一.高分辨扫描透射电子显微镜(STEM),特别是带有球差校正(ac)的高角环形暗场扫描透射电子显微镜(ac-STEM-HAADF)是唯一能够直接"看到"催化剂中单个原子的工具... 详细信息

近年来,"单原子催化"逐渐得到人们的认可与关注,成为催化领域新的前沿与热点之一.高分辨扫描透射电子显微镜(STEM),特别是带有球差校正(ac)的高角环形暗场扫描透射电子显微镜(ac-STEM-HAADF)是唯一能够直接"看到"催化剂中单个原子的工具.在单原子催化的发现、单原子催化剂的开发、催化剂制备的优化、以及单原子催化机理的理解方面具有举足轻重的、甚至是不可替代的作用.本文首先简述了早期的高分辨透射电子显微镜(HRTEM)逐步发展成目前的ac-STEM-HAADF的过程以及过程中各种电镜在单原子观察中的功能.然后综述了ac-STEM在单原子成像、检测单原子分散度及改进催化剂制备参数、检测单原子催化剂中单原子的配位及催化活性中心中的应用及其机遇与挑战.1990年代后期在透镜相差校正领域技术的突破使STEM的分辨率显著提高,因此STEM的单原子成像灵敏度得到明显改善,因而能够对实用催化剂中的单个重原子进行具有很好相衬度的常规检测.2000年代末期刘景月课题组开始进行系统的单原子催化剂合成与表征,表明ac-STEM-HAADF毫无疑问地能够进行实用催化剂中的单个金属原子的常规检测.随后与张涛课题组合作启动了一项采用简便可放大的共沉淀法制备单原子催化剂的项目并取得成功.相比于光谱表征提供样品平均与整体信息,电子显微镜能够提供具有空间分辨的局部信息.对于含有从微米到纳米不同级别不均一性的多相催化剂而言,该技术尤其具有价值.除了能够提供负载金属单原子的空间分布与分散度信息外,如果载体是晶体,ac-STEM-HAADF还能够提供每个金属原子相对于载体表面的空间配位信息.而对于非晶载体例如活性炭、无定型氧化硅等,则以上信息全部丢失,只能提供负载金属原子的空间分布与分散度信息.电子显微镜面临的最主要挑战在于电子束辐射效应:高能电子与样品作用会导致表面金属原子的迁移、表面官能团的消失或改变以及损坏样品等;还会引起环境电镜中气体的离子化.对于大多数催化剂而言,采用低能量电子束能够有效减少电子束辐射影响.由于电子束影响,目前还难以对单原子催化剂进行X射线能量色散谱和电子能量损失谱的常规检测,需要开发更加高效的检测器.此外,电子显微镜只提供三维材料的二维投影,因此在成像过程中不但三维信息丢失,而且对二维投影的解释也具有挑战,因此需要开发具有原子分辨率的三维成像技术.为了更好理解催化剂的制备和催化反应过程,也亟需发展具有单原子分辨率的环境电镜.

关键词：单原子催化球差校正扫描透射电子显微镜探测活性中心

Mesoscale deformation mechanisms in relation with slip and grain boundary sliding in TA15 titanium alloy during tensile deformation

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Journal of Materials Science & Technology 2022年第3期98卷 72-86页

作者： Yanxi Li Pengfei Gao jingyue Yu Shuo Jin Shuqun Chen Mei Zhan State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of High-Performance Precision Forming Technology and EquipmentSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Advanced Functional Materials Education Ministry of ChinaSchool of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China

Revealing the mesoscale deformation mechanisms of titanium alloy with tri-modal microstructure is of great significance to improve its mechanical properties. In this work, the collective behavior and mechanisms of slip activities, slip transfer, and grain boundary sliding of tri-modal microstructure were investigated by the combination of quasi-in-situ tensile test, SEM, EBSD and quantitative slip trace analyses. It is found that the slip behavior presents different characteristics in the equiaxed α(α_(p)) and lamellar α(α_(l))grains. Under a low level of deformation, almost all the slip deformation is governed by single basal and prismatic slips for both of α_(p)and α_(l),despite small amount of -pyramidal slip exists in α_(l)grains. As deformation proceeds, -pyramidal and -pyramidal slip systems with high Schmid factors were activated in quantities. Specially, certain coarse prismatic slip bands were produced across both of single and colony α_(l)grains whose major axes tilting about 40 °–70 ° from the tensile axis. Slip transfer occurs at the boundaries of α_(p)/α_(p)and α_(l)/β under the condition that there exists perfect alignment between two slip systems and high Schmid factors of outgoing slip system. The slip transfer across α_(l)/β boundary can be divided into two types: straight slip transfer and deflect slip transfer with a deviation angle of 5 °–12 °, depending on the alignment of slip planes of two slip systems. The grain boundary sliding along boundaries of α_(l)/β and α_(p)/β was captured by covering micro-grid on tensile sample. It is found that the crystallographic orientation and the geometrical orientation related to loading axis play great roles in the occurrence of grain boundary sliding.

关键词： Titanium alloy Tri-modal microstructure Slip modes Slip transfer Grain boundary sliding

Effect of Mo^(6+)doping on the structure and electrochemical properties of spinel-type LiMn_(2)O_(4)cathode materials

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Particuology 2024年第11期94卷 146-157页

作者： Shengwen Ou Zhen Li Yang You Lianghua Wang jingyue Xu Mingliang Yuan School of Mineral Processing and Bioengineering Central South UniversityChangsha410083China

The Jahn-Teller effect and the dissolution of Mn are significant factors contributing to the capacity degradation of spinel LiMn_(2)O_(4) cathode materials during charging and *** this study,Mo^(6+)-doped polycrystalline octahedral Li_(1.05)Mn_(2-x)Mo_(x)O_(4)(x=0,0.005,0.01,0.015)cathode materials were prepared by simple solid-phase sintering,and their crystal structures,microscopic morphologies,and elemental compositions were characterized and *** results showed that the doping of Mo^(6+)promoted the growth of(111)crystalline facets and increased the ratio of Mn^(3+)/Mn^(4+).The electrochemical performance of the materials was also tested,revealing that the doping of Mo^(6+)significantly improved the initial charge/discharge specific capacity and cycling *** modified sample(LMO-0.01Mo)retained a reversible capacity of 114.83 mA h/g with a capacity retention of 97.29%after 300 ***,the doping of Mo^(6+)formed a thinner,smoother SEI film and effectively inhibited the dissolution of *** density-functional theory(DFT)calculations to analyze the doping mechanism,it was found that doping shortens the Mn-O bond length inside the lattice and increases the Li-O bond *** implies that the Li^(+)diffusion channel is widened,thereby increasing the Li^(+)diffusion ***,the modification reduces the energy band gap,resulting in higher electronic conductivity.

关键词： Mo-doping LiMn_(2)0_(4) Lithium-ion battery

Optimization Scheme of Trusted Task Offloading in IIoT Scenario Based on DQN

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Computers, Materials & Continua 2023年第1期74卷 2055-2071页

作者： Xiaojuan Wang Zikui Lu Siyuan Sun jingyue Wang Luona Song Merveille Nicolas Beijing University of Posts and Telecommunications Beijing100876China China United Network Communications Corporation Beijing Branch 100800China Beijing Information Science and Technology University Beijing100192China University of Quebec at Montreal MontrealH2X 3X2Canada

With the development of the Industrial Internet of Things(IIoT),end devices(EDs)are equipped with more functions to capture ***,a large amount of data is generated at the edge of the network and needs to be ***,no matter whether these computing tasks are offloaded to traditional central clusters or mobile edge computing(MEC)devices,the data is short of security and may be changed during *** view of this challenge,this paper proposes a trusted task offloading optimization scheme that can offer low latency and high bandwidth services for IIoT with data *** technology is adopted to ensure data ***,to reduce the impact of low throughput of blockchain on task offloading performance,we design the processes of consensus and offloading as a Markov decision process(MDP)by defining states,actions,and *** reinforcement learning(DRL)algorithm is introduced to dynamically select offloading *** accelerate the optimization,we design a novel reward function for the DRL algorithm according to the scale and computational complexity of the *** demonstrate that compared with methods without optimization,our mechanism performs better when it comes to the number of task offloading and throughput of blockchain.

关键词： Task offloading blockchain industrial internet of things(IIoT) deep reinforcement learning(DRL)network mobile-edge computing(MEC)

Dynamic response analysis of liquefiable ground due to sinusoidal waves of different frequencies of shield construction

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 637-646页

作者： Wang jingyue Ge Xinsheng Sun Jingyuan Liu Yasheng Shang Zhuo Wang Zhiqiang Tian Maoguo College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030024China The 3rd Engineering Co.Ltd.of China Railway 18th Bureau Zhuozhou 072750China

Vibration induced by shield construction can lead to liquefaction of saturated *** on FLAC3D software,a numerical model of tunnel excavation is established and sinusoidal velocity loads with different frequencies are applied to the excavation *** pattern of the excess pore pressure ratio with frequency,as well as the dynamic response of soil mass under different frequency loads before excavation,is *** the velocity sinusoidal wave acts on the excavation surface of the shield tunnel with a single sand layer,soil liquefaction ***,the ranges and locations of soil liquefaction are different at different frequencies,which proves that the vibration frequency influences the liquefaction location of the *** sand-clay composite strata with liquefiable layers,the influence of frequency on the liquefaction range is different from that of a single *** the frequency range of 5-30 Hz,the liquefaction area and surface subsidence decrease with an increase in vibration *** research results in this study can be used as a reference in engineering practice for tunneling liquefiable strata with a shield tunneling machine.

关键词： shield tunnel liquefiable formation FLAC3D numerical simulation excess pore pressure ratio dynamic response analysis

Modeling study on the roles of the deposition and transport of PM_(2.5) in air quality changes over central-eastern China

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Journal of Environmental Sciences 2023年第1期123卷 535-544页

作者： Lei Zhang Jianjun He Sunling Gong Xiaomei Guo Tianliang Zhao Huizheng Che Hong Wang Chunhong Zhou jingyue Mo Ke Gui Yu zheng Lei Li Junting Zhong Xiaoye Zhang State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Chengdu 610072China Weather Modification Office of Sichuan Province Chengdu 610072China Climate and Weather Disasters Collaborative Innovation Center Nanjing University of Information Science&TechnologyNanjing 210044China

The role of PM_(2.5)(particles with aerodynamic diameters≤_(2.5)μm)deposition in air quality changes over China remains *** using the three-year(2013,2015,and 2017)simulation results of the WRF/CUACE v1.0 model from a previous work(Zhang et al.,2021),a non-linear relationship between the deposition of PM_(2.5)and anthropogenic emissions over central-eastern China in cold seasons as well as in different life stages of haze events was ***_(2.5)deposition is spatially distributed differently from PM_(2.5)concentrations and anthropogenic emissions over *** North China Plain(NCP)is typically characterized by higher anthropogenic emissions compared to southern China,such as the middlelow reaches of Yangtze River(MLYR),which includes parts of the Yangtze River Delta and the ***,PM_(2.5)deposition in the NCP is significantly lower than that in the MLYR region,suggesting that in addition to meteorology and emissions,lower deposition is another important factor in the increase in haze *** transport of pollution in central-eastern China acts as a moderator of pollution levels in different regions,for example by bringing pollution from the NCP to the MLYR region in cold *** was found that in typical haze events the deposition flux of PM_(2.5)during the removal stages is substantially higher than that in accumulation stages,with most of the PM_(2.5)being transported southward and deposited to the MLYR and Sichuan Basin region,corresponding to a latitude range of about 24°N-31°N.

关键词： PM_(2.5) Deposition Regional transport China WRF/CUACE v1.0 model

Direct observation of the impact of water droplets on oil replenishment in EHD lubricated contacts

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Friction 2022年第3期10卷 388-397页

作者： Xiang LIU Jintao WANG Lu HUANG jingyue ZHANG Changhong XU Lin TONG Dan GUO National Institute of Metrology Beijing 100029China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

Water is one of the most significant causes of lubrication *** is little research on the direct observation of the impact of water on lubrication *** this study,the influence of water on oil replenishment under different elastohydrodynamic(EHD)lubricating conditions is evaluated using optical interferometry and infrared microscopy,and a dimensionless criterion when water influences the film thickness is *** shows that the scour displacing effect and emulsification of water/oil are the main reasons for the reduction in film *** a water droplet enters an oil reservoir around the critical contact zone,it hardly moves *** aggravates starvation,reduces the center film thickness of the contact,and leads to lubrication failure of the mechanical components.

关键词： free water droplet point contact starved condition film thickness

Synthesis of Pd Nanocrystals Enclosed by {100} Facets and with Sizes 〈10 nm for Application in CO Oxidation

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Nano Research 2011年第1期4卷 83-91页

作者： Mingshang Jin Hongyang Liu Hui Zhang Zhaoxiong Xie jingyue Liu Younan Xia Department of Biomedical Engineering Washington University St. Louis Missouri 63130 USA Center for Nanoscience University of Missouri St. Louis Missouri 63121 USA State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry Xiamen University Xiamen Fujian 361005 China Department of Physics and Astronomy and Department of Chemistry and Biochemistry University of Missouri St. Louis Missouri 63121 USA

The catalytic activity of noble-metal nanocrystals is mainly determined by their sizes and the facets exposed on the surface. For single crystals, it has been demonstrated that the Pd（100） surface is catalytically more active than both Pd（110） and Pd（111） surfaces for the CO oxidation reaction. Here we report the synthesis of Pd nanocrystals enclosed by {100} facets with controllable sizes in the range of 6-18 nm by manipulating the rate of reduction of the precursor. UV-vis spectroscopy studies indicate that the rate of reduction of Na2PdC14 can be controlled by adjusting the concentrations of Br- and C1- ions added to the reaction mixture. Pd nanocrystals with different sizes were immobilized on ZnO nanowires and evaluated as catalysts for CO oxidation. We found that the activity of this catalytic system for CO oxidation showed a strong dependence on the nanocrystal size. When the size of the Pd nanocrystals was reduced from 18 nm to 6 nm, the maximum conversion rate was significantly enhanced by a factor of -10 and the corresponding maximum conversion temperature was lowered by -80℃.

关键词： Palladium nanocubes CO oxidation size-dependence

Characteristics of sea ice kinematics from the marginal ice zone to the packed ice zone observed by buoys deployed during the 9th Chinese Arctic Expedition

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Acta Oceanologica Sinica 2022年第7期41卷 113-127页

作者： Xiaomin Chang Longchun Ye Guangyu Zuo jingyue Li Keyu Wei Yinke Dou College of Water Resources Science and Engineering Taiyuan University of TechnologyTaiyuan030024China College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan030024China

Sea ice growth and consolidation play a significant role in heat and momentum exchange between the atmosphere and the ***,few in situ observations of sea ice kinematics have been reported owing to difficulties of deployment of buoys in the marginal ice zone(MIZ).To investigate the characteristics of sea ice kinematics from MIZ to packed ice zone(PIZ),eight drifting buoys designed by Taiyuan University of Technology were deployed in the open water at the ice edge of the Canadian *** ice near the buoy constantly increased as the buoy drifted,and the kinematics of the buoy changed as the buoy was frozen into the *** process can be determined using sea ice concentration,sea skin temperature,and drift speed of buoy *** ice concentration data showed that buoys entered the PIZ in mid-October as the ice grew and consolidated around the buoys,with high amplitude,high frequency buoy motions almost *** results confirmed that good correlation coefficient in monthly scale between buoy drift and the wind only happened in the ice *** correlation coefficient between buoys and wind was below 0.3 while the buoys were in open *** buoys entered the ice zone,the buoy speed was normally distributed at wind speeds above 6 m/*** buoy drifted mainly to the right of the wind within 45°at wind speeds above 8 m/*** further consolidation of the ice in MIZ,the direct forcing on the ice through winds will be *** correlation coefficient value increased to 0.9 in November,and gradually decreased to 0.7 in April.

关键词： sea ice kinematics buoy observations remote sensing marginal ice zone

An inflammatory-related genes signature based model for prognosis prediction in breast cancer

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Oncology Research 2023年第2期31卷 157-167页

作者： jingyue FU RUI CHEN ZHIzheng ZHANG JIANYI ZHAO TIANSONG XIA Jiangsu Breast Disease Center The First Affiliated Hospital with Nanjing Medical UniversityNanjingChina

Background:Breast cancer has become the most common malignant tumor in the *** is vital to discover novel prognostic biomarkers despite the fact that the majority of breast cancer patients have a good prognosis because of the high heterogeneity of breast cancer,which causes the disparity in ***,inflammatory-related genes have been proven to play an important role in the development and progression of breast cancer,so we set out to investigate the predictive usefulness of inflammatory-related genes in breast ***:We assessed the connection between Inflammatory-Related Genes(IRGs)and breast cancer by studying the TCGA *** differential and univariate Cox regression analysis,prognosis-related differentially expressed inflammatory genes were *** prognostic model was constructed through the Least Absolute Shrinkage and Selector Operation(LASSO)regression based on the *** accuracy of the prognostic model was then evaluated using the Kaplan-Meier and Receiver Operating Characteristic(ROC)*** nomogram model was established to predict the survival rate of breast cancer patients *** on the prognostic expression,we also looked at immune cell infiltration and the function of immune-related *** CellMiner database was used to research drug ***:In this study,7 IRGs were selected to construct a prognostic risk *** research revealed a negative relationship between the risk score and the prognosis of breast cancer *** ROC curve proved the accuracy of the prognostic model,and the nomogram accurately predicted survival *** scores of tumorinfiltrating immune cells and immune-related pathways were utilized to calculate the differences between the low-and high-risk groups,and then explored the relationship between drug susceptibility and the genes that were included in the ***:These findings contributed to a better understanding of the function

关键词： IRGs Prognostic model TCGA Immune Breast cancer